The present invention relates to a pipe divider for pipes conveying solids of small particle size, comprising a feed pipe, a distributor chamber, and two distributor pipes.
Pipe dividers of this type are known and play an important role in the distribution of solids which are to be conveyed over at least two pipes. However, the substances or substance mixtures to be distributed frequently still contain components which can have a more or less aggressive behavior toward the materials of which these pipe dividers or components thereof are composed in practice. For example, these substances or substance mixtures can, for reasons of production engineering, still contain acids, bases or salts, which can then attack and corrode metals. If, for example, due to the failure of seals, reduced mobility of components or the appearance of holes, such pipe dividers which have become unserviceable must be replaced, this represents not only a cost factor due to the replacement of material but also a possible idling of production units, which today frequently operate continuously. The state of the art has disclosed, for example, the following pipe dividers:
German Auslegeschrift No. 11 65 493 describes a pipe divider for the pneumatic conveyance of dusty or grainy material. The divider has the form of a bifurcated pipe and contains a ball, movable with play, provided as a sealing shut-off means.
German Auslegeschrift No. 12 44 055 discloses a two-way diaphragm divider for solids-laden liquid streams or gas streams, wherein two diaphragm sections, which can be subjected to compressed air for isolating one branch route or the other at will, are provided in the divider housing on both sides of the branching point.
The pipe branch for pneumatic conveying units disclosed by German Auslegeschrift No. 12 50 346 is constructed in such a way that a feed pipe leads into a distributor chamber, from which a plurality of distributor pipes lead away, each distributor pipe having a shut-off means (valve). Cleaning-air nozzles directed onto points with a particularly high risk of deposits lead into the distributor chamber.
German Offenlegungsschrift No. 14 81 189 describes a line system for pneumatic conveying of solids in a carrier gas, which system has one inlet line and at least two outlet lines. Each of the outlet lines contains a valve which is arranged at a certain distance from the branching between the inlet and outlet lines and, in the blocking state, causes the formation of a plug of the solid between the valve and the branch. The plug of solids is removed from the line either automatically when the valve is opened or by means of a flushing gas which is introduced into the system via a flushing gas inlet between the branching and the valve.
German Pat. No. 15 56 320 and No. 17 81 388 disclose a revolving pipe divider for connecting an incoming pipe to one of several outgoing pipes via a revolving pipe, the outlet end of which is connected to the edge zone of a rotary disk, for pivoting about the axis of the inlet pipe.
The pipe divider for the pneumatic conveying of chemically corrosive dusty or grainy materials according to German Offenlegungsschrift No. 19 16 581 comprises a hollow cylindrical housing and a cylindrical cock which is rotatably arranged within the housing. A material feed line and at least two material discharge lines terminate within the shell surface of the housing. The cock of cheap cast material (for example, cast aluminum) contains channels which are formed by pipes of a resistant material (for example, chromium-nickel steel). The other components, coming into interaction with the material of the pipe divider are also made of a resistant material. Additionally, inflatable tubing rings can also be provided for sealing.
Under the demands of practice, however, these pipe dividers still have problems, in particular if the solids to be conveyed and distributed are still moist, so that they tend to cake and/or to stick, or if the solids or dispersion still contain corrosive components. Very frequently, for example, blockages occur in the distributor pipes, or the shut-off means no longer close tightly. It has not been possible hitherto to overcome these problems completely, even by the use of tubing diaphragms, since the latter are very highly stressed mechanically by the solid particles impinging on them in the known arrangements, so that frequent dismantling and refitting or replacement of the pipe dividers are still necessary.